Fireproof fabric and process of making same



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w. G. LINDSAY HSS vi'AEHNG- FIREPROOF FABRIC AND PROCESS oF MAKING SAMEFiled DeC. 14, 1917 n @31g @Hoz/mmf L 0m/rg, Q

Patented Jan.` 20, 1925.

. UNITED STATES" PATENT OFFICE.

WILLIAM G. LINDSAY, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE CELLULOIDCOMPANY, A CORPORATION OF NEW JERSEY.

FIREPROOF FABRIC AND PROCESS OF MAKING SAME.`

Application filed December 14, 1917. Serial No. 207,117.

To all whom it may concer/n.:

Be it known that I, WILLIAM G. LINDSAY, a citizen ofthe United States,residing at Newark, in the county of Essex and State of New Jersey, haveinvented certain new and useful Improvements in Fireproof FabricsaiidProcess'es of Making Same, of which the following is aspecification.

The principal object of my invention is to provide a new and improvedcoated fireproof fabric for use in various places, and

a method of preparing the same. This and f other objects will beindicated in connection with the following specification, in which Ihave disclosed one specific embodiment of my invention and the procedurein accordance therewith.

My improved coated ireproof fabric is especially adapted for use onairplane wings. After the wing frames have been made, the

cloth is ordinarily wrapped once around the frame, sleeve-like, and thencoated with Some varnish-like preparation. It is highly desirable thatthe fabric be fireproof but it is difiicult to obtain this and at thesame time get other desirable characteristics such as waterproofing,strength, exibility, and a proper shrinkage of the fabric so as to drawit on the frame.

Nitrocellulosel or pyroxylin makes a very good coating so far asiiexibility and shrinking effect are concerned, but it is highlyiniammable. By. my invention herein disclosed, I have succeeded indevising a way in which to use such a substance for coating asnitrocellulose and obtain these desirable qualities, but at the same.time make the coated fabric h'reproof as well as waterproof.

Attempts have been made to make a pyroxylin coating fireproof by mixingsome fireproofing ingredient therewith, but such ingredient must bepresent in large proportion to eiiect the desired result, and when it ispresent in this large proportion it detracts from the other desirablequalities of the nitrocellulose.

Stated in somewhat general terms,acco'rd ing to one aspect of myinvention, it involves impregnating the fabric with a fireproofingsubstance and then coating it with a coating of reduced or lowintlammability, whereby the resultant coated fabric will be effectivelytireproof.

'lhe product is shown in the accompanydrawn to such an ordinary degreeof ing drawings, in which Figs. l and 2 are sections, the latterenlarged, of a fabric coated with the resultant composition.

My inventionA may be practiced in a variety of ways; I will now give onespecific f example ofprocedure in accordance thereing formula:

Parts. 4PyroXyl-in 100 Tricresylphosphate 50 Acetone r. 300 Methylalcohol 600 Amyl acetate 300 For the nitrocellulose I use a good solublevariety such as is ordinarily well-known to manufacturers of CelluloidThis pyroxylin solution is then applied with a brush and, after itdries, another coat may be applied if so desired and so on to any numberof coats. In drying it shrinks the fabric so as to draw it tight on theframe; increases its tensile strength, the coating unites intiinatelywith the fabric so as to have unitary character therewith, and leaves asmooth external surface giving a minimum of friction with the air.

In the drawings the fabric is indicated at A, the coating composition atB, C.

The driedammonium phosphate will be in the form of crystals which willadhere to the fibres of the fabric and arrange themselves in irregularmanner. The pyroxylin solution will penetrate into the crevices betweent'he ammonium phosphate crystals and .obviously in many places to thefabric itself. At the same time the crystals will be more or lesssurrounded by and mixed with the pyroxylin thereby forming a more orless intimate mixture between the pyroxylin and the ammonium phosphate,which mixture intimately unites with the fabric to lli.)

106. ceMPeSlTleNs,

COMING ca PLAsuc iis form a unitary structure. If the coating bephysically separated from the fabric it Will carry With it more or lessof the ammonium phosphate. The essential functioning of the substancesis that they cooperate to provide a fireproofer for the fabric and aWaterproofer for the fireproofer and the fabric, the composition alsoacting to shrink the fabric.

The fabric prepared in this Way is effectively fireproof, alsoWaterproof. By Waterprooi I mean not merely that quality which preventsthe passage of Water through the fiexible material but that quality byvirtue of which the surface of the material remains intact, despite itscontinued contact with it, this latter quality resulting from the abovedescribed treatment. I believe that this action is due to the fact thatthe crystals are submerged below the surface. and are protected by thecellulosie composition. The tricresylphosphatc materially reduces theinflammability of the pyroxylin so that the coating alone,-

that is apart from the fabric, would have a low degree ofinflammability. It may be called a coating of low orreducedinfianiinability. By applying this coating to the fireproofedfabric, such as that treated With the ammonium phosphate, the resultantprepared fabric is thoroughlyfireproof.

By suitably varying the process and the ingredients, a variety ofso-called artificial leather may be prepared which, unlike manyartificial leathers, will be non-infiammable. Various other applicationsof the process will suggest themselves, such as for fireprooting sailsand fabrics in various situations.

I have employed various proportions of the tricresylphosphate to thenitrocellulose, using in different cases all the way from 30 to 100parts of the former to 100 parts of the latter. In general, the effectof increasing the amount of tricresylphosphate is to decrease theshrinkage of the fabric and to increase the flexibility of the coating.The present application is a companion to my application, Serial No.207,116, filed December 14, 1917, which application contains genericclaims to features not specifically claimed in the present application.

I claim:

l. The process of making a fircproof coated fabric, which consists infirst impregnating the fabric With a solution of ammonium phosphate,drying out the solvent leaving the salt in the fabric, then i applyingone or more coats of a solution Staf tffftfliltf coated fabric, whichconsists in first impregnating the fabric with ammonium phosphate, thendrying the same, and then coating it with a composition containingpyroXylin.

3. 'Ihe method of preparing a fireproof airplane Wing with a fabricshrunken thereon. which consists in impregnating the fabric With asolution of an inorganic phosphate, and securing it loosely upon thewing frame, drying the fabric, and then coating it with a coating ofpyroxylin and an aromatic phosphate and thereby shrinking it upon theframe.

4. The process of making a fireproof coated fabric, which consists informing thereon in close association pyroxylin, an organic phosphate andan inorganic phosphate in sufficient .quantity to effectnoninfiammability.

5. A fireproof coated fabric comprising a fabric carrying in closeassociation, pyroxylin, an inorganic phosphate and an organic phosphate.

6. A fireproof coated fabric comprising a fabric carrying a fireprofingsubstance containing pyroxylin, ammonium phosphate and an aromaticphosphate. \xk 7. A fireproof coated fabric comprising a fabric carryingin close association pyroxylin, ammonium phosphate andtricresylphosphate.

8. A product comprising a fabric coated with acomposition containing afireprofing substance adapted to give off Water of combination `insufficient quantity to act effectively as. a fire retarder, andpyroxylin.

9. A product comprising a fabric coated with a composition containingammonium phosphate and pyroxylin.

10. A product comprising a fabric coated with a composition containingammonium phosphate, pyroxylin and an inflammability reducer:

11. A Waterproof body having on its surface pyroxylin and a fireretarding constituent adapted to give off a fire smothering gascontaining ammonia.

l2. A waterproof body having on its surface pyroxylin and a fireretardine* constituent adapted to give off water or combination insufficient quantity toi'act effectively as a fire retarder.

13. An article having on its surface a Waterproof material comprisingpyroxyiin and ammonium phosphate.

14. A fireproof body adapted for use Where a Waterproof surface isrequired, said body having a surface material containing as a fireretarder ammonium phosphate and as a protector for the ammonium,pyroxylin.

15. A product containing in close association a compound of ammonia,pyroxylin yand an aromatic pbgsphoric ester.

Search Room mability and in close association. therewith segregated fireextinguishing material.

19. A product consisting of a compound which W11l absorb heat and giveoff water upon decomposition, pyroxylin and tricresg'l:

phosphate in close association.

20. An article having a surface of tough, plastic material, composed ofpyroxylin plasticized by an aromatic phosphate, the said materialcontaining, as a fire retarding agent, ammonium phosphate.

WILLIAM LINDSAY.

